The advice: Even though static stretches just before a workout make you feel more limber, they don't radically improve your flexibility—they just increase your mental tolerance for the discomfort of the stretch, according to some flexibility experts. There are better ways—and times—to limber up, says Lynn Millar, PhD, FACSM, a professor of physical therapy at Winston-Salem State University. "The key is finding moves to improve your range of motion for the activity you're about to engage in—that warm up the body and work the muscles that feel tight," she says. For example, if you're going for a run and you have tight hamstrings, do leg swings and then start jogging at a slow pace. Before a swim, swing your arms in wide arm circles to loosen your shoulders, then do a slow lap to warm up the leg and back muscles. Evidence shows that stretching as part of a regular program decreases risk of injury, so Millar also advises post-activity stretching as part of a cool down. She says this can be done immediately after the workout, or even later that night.